Magnetic actuator and latch



March 11, 1969 G. A. KIM l 3,432,784

MAGNETIC ACTUATOR AND LATCH Filed March l5, 1967 FIG. 4

INVENTOR GEORGE A. KIM

FIG. s BY ATTOBN United States Patent O 3,432,784 MAGNETIC ACTUATOR AND LATCH George A. Kim, Chicago, Ill., assignor to Teletype Corporation, Skokie, Ill., a corporation of Delaware Filed Mar. 15, 1967, Ser. No. 623,341 U.S. Cl. 335-254 13 Claims Int. Cl. H01f 7/00, 7/08 Background of the invention Telegraph and data processing devices frequently employ selector mechanisms for actuating and latching selected one of a plurality of similar members. Typically, selector mechanisms employ cam driven actuators and latches and accordingly can only be used with devices having motors, etc. for providing input motion.

Summary of the invention In the preferred embodiment, a selector mechanism having no components requiring input motion is comprised of a plurality of armature elements, a plurality of actuator electromagnets each individual to one of the armature elements for moving the armature elements to actuated positions and a latch magnet connected in series magnetically with the actuator electromagnets lfor aiding the actuator electromagnets in moving the armature elements and for retaining the armature elements in their actuated positions.

Description of the drawing A more complete understanding of the invention may be had by referring to the following ydetailed description when taken in conjunction with the drawing herein:

FIGURE 1 is a side view of a magnetic actuator and latch mechanism employing the present invention in which certain parts have been broken away more clearly to illustrate certain features of the invention;

FIGURE 2 is a top view of the device shown in FIG- URE 1 in which certain parts have been broken away more clearly to illustrate certain features of the invention;

FIGURE 3 is an enlarged, partial sectional view taken along the line 3-3 in FIGURE l in the `direction of the arrows, and

FIGURE 4 is a schematic illustration of a circuit which l may be employed in the operation of the device shown in FIGURES l, 2, and 3.

Detailed description Referring now to the drawing, wherein like reference numerals designate like parts throughout the several views, with particular reference being had to FIGURE 1, there 3,432,784 Patented Mar. l1, 196

is shown a magnetic actuator and latch mechanism including a Ibase plate 10 upon which a magnetic insulator plate 11, formed from copper or the like, is mounted. A latch magnet 12, including a core 13 and an energizing coil 14 mounted on the core 13, is supported on the magnetic insulator plate 11 and extends upwardly therefrom.

Also mounted on the magnetic insulator plate 11 is a core extention plate 15 which is connected in series magnetically with the core 13 of the latch magnet 12. Mounted on the extension plate 15 is a magnetic insulator plate 16 formed from copper or the like Iwhich in turn supports a plurality of actuator electromagnets 17. The actuator electromagnets 17 are each comprised of a core 18 and an actuating coil 19 positioned on the core. The cores 18 of the actuator magnets 17 extend vertically from the insulator plate 16 and are each connected in series magnetically with core 13 of the latch magnet 14 by a bridge 20 formed from a magnetically conductive material.

The core extension 15 has a shallow, U-shaped groove lformed in its end remote from the core 13. A plurality of armature members 21 each individual to one of the actuator electromagnets 17 and each aligned with a foot 22 of its associated core 18 are pivotally supported in the -shaped groove of the extension 15 and, accordingly, are connected in series magnetically with the core 13 of the latch magnet 12. The armatures 21 for each individually connected by a pin 23 to a sli-der member 24. The slider members 24 are slideably supported on pins 25 and are urged to the left (FIGURE 1) by armature return springs 26 which operate through the sliders 24 and the pins 23 to urge the armatures 21 away from their associated core feet 22.

Referring now to FIGURE 4, a circuit for operating the device shown in FIGURES l, 2 and 3 is schematically illustrated. The coil 14 of the latch magnet 12 is initially connected to a battery 27 by means of a knife switch 28. Energization of the coil 14 induces iiux in the cores 18 of all of the actuator magnets 17 by means of the bridge 20. The strength of the battery 27 and the reluctance of the coil 14 of the latch magnet 12 are selected so that the amount of flux induced in the cores 18 upon energization of coil 14 is insutlicient to move the armatures 21 into engagement with their associated core feet 22 against the actions of the springs 26.

Whenever actuation of a selected armature 21 is desired a push button 29 associated with the coil 19 of the actuator electromagnet 17 associated with the selected armature 21 is depressed. This connects the coil 19 of the selected electromagnet 17 to the battery 27 which in turn induces additional flux in the core 18 associated with the selected armature 21. The reluctance of the coils 19 is selected so that energization of a particular coil induces an amount of ilux in the core 18 which, when added to the flux induced in the core 18 by the latch magnet 12, is of suiiicient magnitude to move the selected armature 21 into engagement with its associated core foot 22 against the action of its associated armature return spring 26.

After a selected armature 21 has been moved into engagement `with its associated foot 22 by operation of its associated actuator magnet 17 the push button 29 associated with the selected armature 21 is released. The flux induced in the cores 18 by energization of the latch magnet 12 is suiilcient to retain the selected armature 21 in its actuated position since the air gap separating the foot 22 of the selected armature 21 has been considerably reduced.

once selected, the armatures are retained in Je actuated position by the latch magnet 12.

Selected armatures 21 may be actuated in groups rather nan singly by simply depressing two or more push butons 29 simultaneously. Also, selected armatures 21 may e actuated sequentially by depressing the push buttons 29 ither singly or multiply in any preselected pattern. It has )een found that if multiple armature actuation is desired t is desirable to place magnetic insulators formed from :opper or the like between the core feet 22 to prevent )ridging of flux generated by selected actuator magnets 17 nto the cores 18 of unselected actuator electromagnets.

After the selected armatures 21 have been moved t0 :heir actuated positions all of the actuated armatures 21 are returned to the 'position shown in the drawing by opening the knife switch 28. This eliminates all ux from the cores 18 of the actuator electromagnets 17 whereupon the armature return springs 26 return the selected armatures 21 to their deactuated positions.

Although only one embodiment of the invention is shown in the drawing and described in the foregoing specification, it will be understood that the invention is not limited to the specific embodiment described but is capable of modification, rearrangement and substitution f parts and elements without departing from the spirit of invention. One particular modification which may frequently be desirable is the substitution for the core 13 of the magnet 12 of a permanent magnet for inducing ux in the cores 18. If such a substitution is made the coil 14 is wound in a manner such that energization of the coil 14 cancels the ux generated by the permanent magnet so that previously the selected armatures 21 are returned to their deactuated positions.

What is claimed is:

1. A magnetic actuator and latch mechanism including:

a plurality of actuator electromagnets each having a core and each having an armature mounted for movement to an actuated position in response to the presence of a predetermined amount of flux in the core;

a latch magnet connected in series magnetically with the core of each of the actuator electromagnets for inducing an amount of ilux less than the predetermined amount in the core of each of the actuator electromagnets;

energizing means for inducing additional ilux in the core of at least one of the actuator electromagnets to bring the amount of flux in the core of the one of the actuator electromagnets to the predetermined amount thereby moving the armature of the one of the actuator electromagnets to its actuated position.

2. The magnetic actuator and latch according to claim 1 further including means extending from the latch magnet to a position adjacent the cores of the actuator electromagnets for connecting the armatures of the actuator electromagnets in series magnetically with the latch magnet.

3. The magnetic actuator and latch mechanism according to claim 1 further including means for urging the armatures of the actuator electromagnets away from their actuated positions and wherein flux generated in the cores of the actuator electromagnets by the latch magnet is of sufficient magnitude to retain the armatures in their actuated positions against the action of the urging means after the armatures have been moved to their actuated positions by operation of the energizing means.

4. The magnetic actuator and latch mechanism according to claim 3 further including means for stopping the induction of flux in the cores of the actuator electromagnets by the latch magnet;

said urging means also for moving the armatures of the actuator electromagnets away from their actuated positions upon operation of the stopping means.

5. A magnetic actuator and latch mechanism including:

a plurality of actuator electromagnets each having a core;

latch magnet means for inducing a first predetermined tccordingly,

amount of flux in the core of each of the actuator electromagnets;

a plurality of armatures each individual to one of the actuator electromagnets and each mounted for movement from a deactuated posltion to an actuated position in response to the induction in the cores of their respective actuator electromagnets of a second predetermined amount of ux;

means for resisting movement of the armatures from the deactuated position to the actuated position and for preventing movement ofthe armatures to the actuated position in response to the presence of the first predetermined amount of ux in the cores of the actuator electromagnets; and

energizing means for causing selected ones of the actuator electromagnets to induce additional flux in their cores of sufficient magnitude to make the total amount of flux in their cores at least equal to the second predetermined amount of flux thereby moving the armatures associated with the selected actuator electromagnets to their actuated positions against the action of the resisting means.

6. The magnetic actuator and latch mechanism according to claim 5 wherein the first predetermined amount of flux induced in the core of each actuator electromagnet by the latch magnet is of sufficient magnitude to retain the selected armature members in their actuated lpositions against the action of the resisting means after the energizing means has caused the selected actuator electromagets to move their associated armature members to their actuated positions.

7. The magnetic actuator and latch mechanism according to claim 6 further including unlatching means for causing the latch magnet to stop inducing the first predetermined amount of flux in the core of each actuator electromagnet, said resting means also for moving the selected armature members to their deactuated positions upon operation of said unlatching means.

8. A magnetic actuator and latch mechanism including:

a plurality of actuator electromagnets each having a core;

at least one latch electromagnet having a core;

means for magnetically linking the cores of each of the actuator electromagnets to the core of the latch electromagnet;

a plurality of armature members each individual to one of the actuator electromagnets and each mounted for movement toward and away from the core of its associated electromagnet;

means for resisting movement of the armature members toward the cores;

energizing means for causing the latch electromagnet to induce magnetic flux in its core thereby inducing magnetic flux in the cores of each of the actuator electromagnets; and

energizing means for causing selected ones of the actuator electromagnets to induce in their cores additional magnetic uX of suflicient magnitude to move the armature members associated with the selected actuator electromagnets toward the cores of their associated actuator electromagnets against the action of the resisting means.

9. The actuator and latch mechanism according to claim 8 wherein the ux induced in the cores of the actuator electromagnets by the latch electromagnet is of Sufficient magnitude to prevent the armatures of the selected actuator electromagnets from moving away from their respective cores upon the de-energization of the actuator electromagnets.

1t). The actautor and latch mechanism according to claim 8 further including a latch electromagnet core extension formed from magnetic material and extending adjacent the cores of the actuator electromagnets and wherein the armature elements are pivotally supported on said core extension.

11. In a selector mechanism of the type including a plurality of individual electromagnets each including an armature mounted for movement from a first position to a second lposition by its associated electromagnet, the improvement characterized by means for inducing flux in all of the electromagnets of sucient magnitude to retain in the second position any armature moved to the second position by its associated electromagnet.

12. The selector mechanism according to claim 11 wherein the tlux inducing means is comprised of a latching electromagnet and means for directing flux generated by the latching electromagnet into each of the individual electromagnets.

13. The selector mechanism according to claim 12 further including means for causing selected one of the individuall electromagnets to generate magnetic llux that adds to the flux directed to the selected electromagnets by the latching electromagnet thereby moving the armature associated with the selected electromagnets to their secon positions.

References Cited UNITED STATES PATENTS 1,131,982 3/1915 Ackerman 335-234 XI 1,800,973 4/1931 Wusteney 178-31 2,756,372 7/1956 Martindell 335-23 FOREIGN PATENTS 498,039 12/1953 Canada.

G. HARRIS, Primary Examiner.

U.S. C1. X.R. 178-33; 335-268 Disclaimer 3,432,784f-Ge07ge A. Kim, Chicago, Ill. MAGNETIC ACTUATOR AND LATCH. Patent dated Mar. 11, 1969. Disclaimer filed Apr. 9, 1970, by the assignee, Teletype Corporation. Hereby enters this disclaimer to claim 11 of said patent.

[Official Gazette DecembeT 8, 1970.] 

